JP2001046957A - Method of coating ship or steel structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent occurrence of return rust without obstructing the sticking property of a top coating material by top-coating after treating the whole surface of a ship or a steel structure having the surface coated with a zinc based shop primer and constructed by welding a steel material with water blast. SOLUTION: The 1st coating method is executed by treating, for example, the whole surface of the ship or the like constructed by welding the steel materials having the surface coated with a zinc based shop primer with the water blast using the particles of a metal baser than iron and an inorganic fine particle as abrasive and after that, top-coating. The 2nd coating method is executed by treating the surface with the water blast in, for example, the repair coating of the ship or the like and after that, top-coating. The degraded part and the rust on the primer coating film or various foreign matter, corrosive materials or the rust stuck on the surface of steel material are completely and easily removed, and occurrence of the return rust is prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for coating a ship or a steel structure.

[0002]

2. Description of the Related Art Conventionally, in the surface treatment of steel structures such as ships, or steel structures such as towers and bridges (excluding ships) by water blasting, after performing rust prevention treatment and cleaning of the steel surface, In the process of drying moisture, rust is generated again, so-called "turning rust (turning)", and if normal coating is performed on the returning rust, this returning rust may adversely affect the adhesion of the coating film. I am concerned.

[0003] Therefore, a rust preventive agent or the like is added in advance to the water used for the water blast treatment, so that "return rust" is reduced.
Many techniques have been proposed to prevent the occurrence of blemishes. However, most of the rust preventives used in these technologies are alkaline, and when using an alkaline rust preventive, although "return rust" does not occur, there are those that hinder the adhesion of the topcoat paint. Many.

[0004] Incidentally, for example, a steel material carried into a shipyard is subjected to a primary surface treatment combining shot blasting and coating with a primer which is an inorganic zinc-based paint, and then subjected to internal processing and assembly. Have been. After assembling such a steel material, a secondary surface treatment is conventionally performed on a rusted portion of the steel material by a combination of sandblasting or sanding and coating with the same primer as described above.

[0005] Recently, while improving the performance of the primer in the primary surface treatment, the "rust-free method"
In order to minimize the rusting of the damaged part of the primer, the rusting of the rusted part is minimal in the secondary surface treatment. It mainly removes marks, soluble salts (chloride, sulfide, etc.), dust and the like.

However, ships such as water
Painting on the inner surface of the ballast tank is concerned with the safety of the ship, and it is expected that the service life will be prolonged because repair painting is difficult after service. Therefore, when newly constructing a ship, it is necessary to sufficiently perform substrate adjustment as a secondary surface treatment, which is a pretreatment, and painting with an appropriate paint. In addition, coating defects occurring after the service actually occur at welded seams and sharp edges where it is difficult to adjust the base material and properly apply the coating.

Conventionally, the base adjustment has been performed by a combination of sandblasting and sanding. However, in these treatments, it is actually difficult to remove corrosive substances present in small pits or holes and to perform uniform surface treatment. Furthermore, the inside of the water ballast tank is not only restricted in its work due to its structure, but also requires a severe labor due to the large area to be painted.In addition, dust is scattered in sandblasting and sanding. As a result, the working environment is poor, and post-treatment of carrying out the dust is required.

Therefore, when a new ship or steel structure is manufactured, heat scale, spatter, and the like adhered during the construction of the ship or steel structure without damaging the primer coating formed by the primary surface treatment. It is possible to completely or almost completely remove various foreign matters, corrosive substances, degraded portions of the primer coating and rust generated by damage to the primer coating, and to carry out post-treatment of carrying out dust. A method for painting a ship or steel structure capable of improving the working environment without reducing or requiring it, preventing the occurrence of return rust without impairing the adhesion of the topcoat paint, and a ship or steel When repairing and painting the surface of a structure, completely or almost completely remove various foreign substances, corrosive substances and rust adhering to the steel surface A ship or ship that can be easily made, does not require a post-treatment of carrying out dust, can improve the working environment, and can prevent the generation of return rust without inhibiting the adhesion of the topcoat paint. The emergence of a method for painting steel structures is desired.

[0009]

SUMMARY OF THE INVENTION An object of the present invention is to solve the problems associated with the prior art described above, and when a new ship or steel structure is manufactured, a primer coating formed by a primary surface treatment is used. Heat scale, spatter, which adheres during the construction of ships and steel structures without damaging the film
It is possible to completely or almost completely remove various foreign matters, corrosive substances, degraded portions of the primer coating and rust generated by damage to the primer coating, and to carry out post-treatment of carrying out dust. A method for painting a ship or steel structure capable of improving the working environment without reducing or requiring it, preventing the occurrence of return rust without impairing the adhesion of the topcoat paint, and a ship or steel When repairing and painting the surface of a structure, it is easy to completely or almost completely remove various foreign substances, corrosive substances and rust adhering to the surface of the steel material, and it is possible to improve the working environment. It is an object of the present invention to provide a method for coating a ship or a steel structure capable of preventing return rust without inhibiting the adhesion of a top coat paint. .

[0010]

SUMMARY OF THE INVENTION A first embodiment of a ship or steel structure according to the present invention
Is characterized in that a water blast treatment is applied to the entire surface of a ship or a steel structure assembled by welding a steel material having a surface coated with a zinc-based shop primer, and then a top coat is applied.

In this water blast treatment, a zinc-based anticorrosive paint is applied to a damaged portion of the paint of the zinc-based shop primer of a ship or a steel structure assembled by welding a steel material having a surface coated with a zinc-based shop primer. After up-painting, it is preferable to apply it to the entire surface of the ship or steel structure. In addition, after water blasting is applied to the entire surface of a ship or steel structure assembled by welding steel with a zinc-based shop primer applied to the surface, the coating of the zinc-based shop primer is damaged, the welded seam and the sharp It is also preferable to apply a top-coating paint after the touch-up coating of the anticorrosion paint having an affinity for the base material and the top-coat paint on the edge portion.

In the first method for coating a ship or a steel structure according to the present invention, the method includes
It is preferable to blast the abrasive (A) together with water. As the abrasive material (A), an abrasive material composed of particles (a1) of metal lower than iron is preferable, and in particular, metal particles (a1) lower than iron and inorganic fine particles (a2) other than metal.
A polishing material comprising a mixture of

In the water blast treatment, water containing a corrosion inhibitor (B) can be used. The water containing the corrosion inhibitor (B) is preferably blasted together with the abrasive (A). The water pressure in the water blast treatment is about 0.1 to 300
It is preferably MPa. The pressure of the water blast treatment using only water is usually from 10 to 300 MPa, preferably from 150 to 250 MPa, and the pressure of the water blast treatment using the abrasive (A) is usually from 0.1 to 30 MPa.
It is 0 MPa, preferably 0.3 to 200 MPa.

A second method of coating a ship or a steel structure according to the present invention is a method of repairing a surface of a ship or a steel structure which is assembled by welding steel materials. It is characterized by applying a water blast treatment for blasting and then top-coating. As the abrasive material (A), metal particles (a
A cleaning material composed of 1) is preferable, and particularly a polishing material composed of a mixture of metal particles (a1) which are lower than iron and inorganic fine particles (a2) other than metal is preferable.

In the water blast treatment, water containing a corrosion inhibitor (B) can be used. The water containing the corrosion inhibitor (B) is preferably blasted together with the abrasive (A). Water pressure in the water blasting process is about 0.1-300M
It is preferably Pa. The pressure of the water blast treatment using only water is usually 10 to 300 MPa, preferably 150 to 250 MPa, and the pressure of the water blast treatment using the abrasive (A) in combination is usually 0.1 to 300 MPa.
MPa, preferably 0.3 to 200 MPa.

[0016]

DETAILED DESCRIPTION OF THE INVENTION Hereinafter, the first and second coating methods for a ship or a steel structure according to the present invention will be described in detail. First coating method for ship or steel structure The first method for coating a ship or steel structure according to the present invention comprises:
This is a coating method applied when newly manufacturing a ship or steel structure.Water blast treatment is applied to the entire surface of a ship or steel structure assembled by welding steel with a zinc-based shop primer applied to the surface. After that, the top coat is applied.

In this coating method, the water blast treatment is performed by applying a zinc-based anticorrosive paint to the damaged portion of the paint of the zinc-based shop primer applied to the surface of the ship or steel structure, and then applying the paint to the ship or steel structure. Preferably, it is performed over the entire surface of the structure. In addition, after water blasting is applied to the entire surface of a ship or a steel structure assembled by welding a steel material applied to the surface with a zinc-based shop primer, the coating film damaged portion of the zinc-based shop primer, a welded seam portion and It is also preferable that the sharp edge portion is subjected to touch-up coating with an anticorrosive paint having, for example, affinity with the base material and the top coat, and then a top coat is applied. The coating damage of the zinc-based shop primer is almost caused by welding or fusing.

[Zinc-based shop primer] The zinc-based shop primer (zinc-based primary rust-preventive paint) used for applying to the surface of a steel material in the present invention may be an organic zinc-based primary rust-proof paint or an inorganic zinc-based paint. It may be a zinc-based primary rust preventive paint. Examples of the organic zinc-based primary rust preventive paint include an epoxy zinc primer and the like, and examples of the inorganic zinc-based primary rust preventive paint include an inorganic zinc such as a silicate-based binder, particularly an inorganic zinc-based binder using a silicate-based binder. It is preferable to use a primary rust preventive paint. In particular, when an organic zinc-based primary rust preventive paint is used, a coating film having a uniform film thickness and excellent corrosion resistance can be obtained, and the amount of paint to be applied to the surface of the primary rust preventive paint film can be reduced. . In addition, when an inorganic zinc-based primary rust preventive paint is used, a coating film having excellent weldability, a uniform film thickness, and excellent corrosion resistance can be obtained. Among these zinc-based shop primers, inorganic zinc-based primary rust preventive paints are particularly preferred.

The epoxy zinc primer preferably has a nonvolatile content of 25 to 35% and a zinc concentration by weight of 50 to 90% in the coating film. The inorganic zinc-based primary rust preventive paint contains a silicate-based binder and zinc dust as a rust preventive pigment, and has a non-volatile content of 1%.
7 to 27%, and the zinc concentration by weight in the coating film is 20 to 95%.
It is preferable that

In the present invention, when a rust-preventive paint other than a zinc-based shop primer is used as a shop primer, return rust easily occurs. However, the above-mentioned zinc-based shop primer, in particular, an inorganic zinc containing a silicate-based binder is used. If a primer film made of a system primary rust preventive paint is formed on the surface of a steel material, even if the primer film is damaged, return rust is less likely to occur due to the anticorrosive effect of zinc.

The coating method of the zinc-based shop primer as described above is not particularly limited, and a conventionally known coating method can be employed. The coating of the zinc-based shop primer is usually performed after removing the scale by performing shot blasting on the surface of the steel material. [Ship and Steel Structure] As the ship in the present invention,
Specific examples include passenger ships, cargo ships, tankers, etc.
As steel structures other than ships, specifically, towers, bridges,
Offshore structures, oil drilling plants, various plant large structures, and the like.

[ Zinc-based rust-proof coating for touch-up coating
Materials] Examples of the zinc-based rust-preventive paint used in the touch-up coating performed as needed before the water blast treatment include, for example, the same organic or inorganic zinc-based primary rust-preventive paint as the above-mentioned zinc-based shop primer. . In particular, a primary rust preventive paint using a silicate-based binder is preferred.

The touch-up coating as described above can be performed by using a conventionally known touch-up coating method. In this specification, so-called stripe coating is also included in touch-up coating as long as coating is performed from rust generated on steel materials. In the present invention, by applying a touch-up coating on the rust generated on the steel material with a zinc-based rust-preventive paint, the range of rust is prevented from further expanding due to the electrochemical anticorrosion effect of zinc in the paint. And also facilitates cleaning.

[Water Blast Treatment] In the above water blast treatment, water is blasted, but it is preferable to blast the abrasive (A) together with water. Examples of the abrasive material (A) include metal particles (a1) that are lower than iron, inorganic fine particles (a2) other than metal, and metal particles (a1) lower than iron and inorganic fine particles (a2) other than metal. )
And mixtures thereof.

The metal particles (a1) which are more base than iron mean metal particles having a higher ionization tendency than iron, such as particles of zinc, aluminum and the like. Among them, it is preferable to use zinc particles. These metal particles (a1) can be used alone or in combination of two or more. The average particle diameter of such metal particles (a1) which are more base than iron is usually 0.1 to 3000.
μm, preferably 1 to 300 μm. Abrasive material (A)
When metal particles (a1) that are more base than iron, such as zinc particles, are used, the metal particles (a1) adhere to the surface of the steel material subjected to the water blast treatment, and return rust (turning) occurs due to an electrical anticorrosion effect. Can be prevented. When a zinc-based shop primer, particularly a zinc-based shop primer containing a silicate binder, is used as the shop primer, the effect of preventing the generation of this return rust is enhanced.

The inorganic fine particles (a2) other than metal include:
For example, fine particles such as garnet and quartz sand are included.
These inorganic fine particles (a2) can be used alone or in combination of two or more. The average particle diameter of such inorganic fine particles (a2) is usually 50 to 30.
00 μm, preferably 300 to 1000 μm. The heat scale adhered to the welding point and welding line and the scale generated by exhaustion of spatter and shop primer cannot be completely removed by blasting using only water. When water blasting is carried out in combination with inorganic fine particles (a2) other than metals such as garnet and silica sand as A), heat scale, spatter, and scale can be easily or almost completely removed. In this case, when metal particles (a1) lower than iron, such as zinc particles, are used in combination, it is possible to chemically or electrochemically return and prevent rust.

When only the metal particles (a1) that are lower than iron are used as the abrasive (A), the metal particles (a1) that are lower than iron are usually 1 to 1000% by volume, preferably 1 to 1000% by volume, based on water. Is used at a rate of 10 to 30% by volume. When only the inorganic fine particles (a2) other than the metal are used as the abrasive material (A), the fine particles (a2) other than the metal have a ratio of usually 1 to 1000% by volume, preferably 10 to 30% by volume with respect to water. Used in

In the case where a mixture of metal particles (a1) that are lower than iron and inorganic fine particles (a2) other than metal is used as the abrasive (A), the metal particles (a1) that are lower than iron are mixed with water. On the other hand, usually 1 to 1000% by volume, preferably 10 to
It is used at a ratio of 30% by volume, and the inorganic fine particles (a2) other than metal are used at a ratio of usually 1 to 1000% by volume, preferably 10 to 30% by volume, based on water.

Corrosion inhibition during water blasting
It is desirable to add the agent (B) to water. This corrosion
The inhibitor (B) forms a protective film on the metal surface and protects against corrosive substances.
It is a chemical that prevents erosion, and is a known corrosion inhibitor.
An agent (corrosion inhibitor) can be used. Concrete
Typically, sodium chromate (Na_TwoCrO_Four), Heavy black
Sodium oxalate (Na_TwoCr_TwoO ₇・ 2H_TwoChrome such as O)
Acid salt, sodium nitrite (NaNO_Two) And other nitrites,
Molybdate, tungstate, benzoate, etc.
Anode type (anode type) inhibitors;
Cathode-type (cathode-type) inhibitors such as sulfonic acid and zinc salt
The same polar and hydrophobic groups with affinity for metal
Bipolar type such as amines and surfactants in the molecule
Inhibitors can be mentioned. These corrosion controls
Agent (B) may be used alone or in combination of two or more.
Can be used. As such a combination
Is, for example, a combination of chromate and polymerized phosphate
A combination of a polymeric phosphate and a zinc salt.
You.

The concentration and pH of the corrosion inhibitor (B) added to water cannot be unambiguously specified, but are appropriately determined depending on the type. For example, sodium chromate has an addition concentration of usually 300 to 500 ppm and a pH of 8.5.
It is used under the following alkaline conditions. The concentration of sodium nitrite is usually about 50 ppm,
It is preferable to use 9 to 10 alkaline.

There is a concern about the occurrence of return rust in the water blast treatment of the steel material. However, in the case of the ultra-high pressure water blast treatment, the temperature of the steel material sprayed with water or the like is increased, and the drying speed is reduced to the ordinary water speed. Return rust hardly occurs due to the faster blasting process and the electrolytic protection effect of the zinc-based shop primer used for the primary surface treatment. Therefore, in the present invention, the water blast treatment is preferably performed at about 0.1 to 300M.
It is performed at a water pressure of Pa. The pressure of the water blast treatment using only water is usually 10 to 300 MPa, preferably 1 to 300 MPa.
The pressure of the water blast treatment using the abrasive material (A) in combination is usually 0.1 to 300M.
Pa, preferably 0.3 to 200 MPa. Also,
The amount of water is preferably 5 to 50 l / min.

The water blast treatment can be performed using a conventionally known water jet gun.
Furthermore, if the gun has a structure such that when the water or the water containing the corrosion inhibitor (B) is sprayed from the nozzle of the gun, the granular abrasive (A) can be simultaneously sprayed with the water. , Any gun. Further, when the use ratio of the abrasive material (A) is large, a high-pressure air jet gun using high-pressure air is also conveniently used.

By performing the rust-proofing treatment using the zinc-based shop primer, the water blasting treatment, and the touch-up coating as required, it is possible to impart excellent long-term corrosion protection to ships and steel structures. [Touch-up coating after water blast treatment] Non-tar epoxy resin paint is used as the anti-corrosion paint used for touch-up coating on the paint damaged part, welded seam and sharp edge part of zinc-based shop primer after water blast treatment. And a tar-based epoxy resin paint, a urethane resin paint and the like. Among these anticorrosion paints, tar epoxy resin paints having high affinity for the base and top coat paints are particularly preferred. As such a tar-based epoxy resin paint,
For example, JP-B-62-36073, JP-B-62-36073
No. 47907 and JP-B-3-49949.

The anticorrosion coating composition disclosed in Japanese Patent Publication No. 62-36073 comprises (i) an epoxy resin represented by the following general formula (1) and a polyhydric phenolcarboxylic acid polyhydric alcohol ester having an adjacent hydroxyl group. Or a high molecular weight reaction product obtained by reacting a polynuclear polyphenol having an adjacent hydroxyl group with a solvent (modified epoxy resin)
And (ii) a bituminous substance and (iii) a polyisocyanate compound having more than one isocyanate group in one molecule as a coloring agent.

[0035]

Embedded image

Wherein R ¹ is H or CH ₃ ,
² is -CH ₂ - or -C (CH _{3) 2} - a and, n represents 3
0 to 200. The polyhydric alcohol esters of polyhydric phenol carboxylic acids having adjacent hydroxyl groups include polyhydric alcohols such as ethylene glycol, propylene glycol and pentaerythritol, catechol-3-carboxylic acid, gallic acid and pyrogallol-4,6-dicarboxylic acid. An ester compound with a polyhydric phenol carboxylic acid such as an acid.

As the above bituminous substance, for example, coal powder is mixed with coal tar and coal tar pitch.
So-called swollen charcoal, which is swollen at a high temperature of 00 ° C or more, may be mentioned. The anticorrosion coating composition disclosed in Japanese Patent Publication No. 62-47907 is (i) n in the above general formula.
Is an epoxy resin represented by the same formula except that is 5 to 30, and a polyhydric phenol carboxylic acid having an adjacent hydroxyl group,
A high molecular weight reaction product (modified epoxy resin) obtained by reacting a polyhydric phenol polyhydric alcohol ester having an adjacent hydroxyl group or a polynuclear polyhydric phenol having an adjacent hydroxyl group in a solvent, and (ii) a bituminous substance; , (Iii) zinc chromate as an essential component.

Examples of the above polyhydric phenol carboxylic acid having an adjacent hydroxyl group include catechol-3-carboxylic acid, gallic acid, pyrogallol-4,6-dicarboxylic acid and the like. Examples of the polynuclear polyphenol having an adjacent hydroxyl group include catechol, pyrogallol, and tannic acid.

The anticorrosion paint disclosed in Japanese Examined Patent Publication No. 3-49949 has the following properties: (i) In the above general formula, n is 5 to 3;
A high-molecular-weight reaction product obtained by reacting an epoxy resin represented by the same formula with a polyhydric phenol carboxylic acid polyhydric alcohol ester having an adjacent hydroxyl group or a polynuclear polyhydric phenol having an adjacent hydroxyl group in a solvent except that it is 0. (Modified epoxy resin), (ii) 30 to 600 parts by weight of a coal-based bituminous substance, and (iii) liquid synthetic rubber 0 to 50 having a weight average molecular weight of 200 to 50,000.
% By weight.

Examples of the above liquid synthetic rubber include butadiene, chloroprene and neoprene (registered trademark).
And homo- or copolymers of compounds having at least one conjugated double bond selected from the group consisting of: The color of these anticorrosion paint compositions is preferably light. This is because touch-up coating with a light-colored anticorrosive coating composition facilitates visual detection of pits (pits), undercuts, cracks, and the like on the steel sheet surface.

These anticorrosion coating compositions are suitable as heavy anticorrosion coatings for coating on ships, especially on the inner surfaces of tanks.
It can be used as an anticorrosive paint for oil storage tanks, various onshore plants, bridge girder inner surfaces, and other steel structures. When touch-up painting is performed on the rust generated on the surface of the steel material with the above anticorrosive paint, the range of the rust can be prevented from expanding. Such touch-up coating is suitable for the inner surface coating of ship outer panels and ship tanks, especially ballast tanks such as water ballast tanks.

This touch-up coating can be performed by a conventionally known touch-up coating method. As anticorrosion paints used in touch-up coating, for example, "Vismax" (modified tar epoxy resin paint), "Yumeguard PU" (modified epoxy urethane resin paint), and "Yumeguard PU-TU" (epoxy) from China Paint Co., Ltd. Examples include anticorrosion paints commercially available under the trade names of “polyurethane resin paint”, “Super Bondex T” (modified epoxy resin paint), and “Yumeguard SX” (modified epoxy resin).

[Overcoating] The overcoating used in the overcoating after the water blast treatment or after the touch-up coating with the above anticorrosive coating is a coating other than the above-mentioned zinc-based shop primer. In the case of a ship, its outer panel is located between the bottom of the vessel, which is always immersed in water (including freshwater and seawater), and the outer hull, which is not immersed in water. Are repeated.

Since the waterline of a ship is exposed to a harsh environment that is subjected to a dry / wet interaction between immersion in seawater and air exposure, weather resistance, water resistance and, if necessary, antifouling properties are required. Is done. Therefore, as a top coating for the water line part,
Urethane-based, epoxy-based, acrylic-based, chlorinated polyolefin-based (chlorinated rubber-based) paints or non-organic tin-based antifouling paints are preferred, and epoxy-based paints and non-organic tin-based antifouling paints are particularly preferred. Specifically, isocyanate cross-linking type two-pack type urethane resin-based topcoat "Unimarine (trade name)"
(Manufactured by China Paint Co., Ltd.), modified polyamidoamine crosslinked type 2
"Epicon Marine Topcoat (trade name)" (China Paint Co., Ltd.), "Epicon Marine HB (trade name)" (China Paint Co., Ltd.), chlorinated polyolefin-based topcoat paintの 「ラ バ ッ ク ス 上 覆 （Product name）」
(Manufactured by China Paint Co., Ltd.) and acrylic resin-based overcoat “Acry 700 Topcoat (trade name)” (manufactured by China Paint Co., Ltd.).

As the non-organic tin antifouling paint, for example, a non-organic tin antifouling paint described in JP-A-10-212164, that is, (i) a trialkylsilyl ester copolymer, or ( ii) a resin in which an organic acid is bonded to at least one side chain terminal of a vinyl resin via a metal ester bond such as a copper ester bond, for example, a copolymer containing an unsaturated carboxylic acid copper salt component, (iii) (meth)
Those containing a polymerizable unsaturated zinc carboxylate component-containing copolymer, such as a hydroxyzinc acrylate copolymer or a zinc (meth) acrylate copolymer, may be mentioned.

The outboard portion of a ship is exposed to strong sunlight and wind waves, and is required to have weather resistance and the like. Therefore, urethane-based, epoxy-based,
Acrylic and chlorinated polyolefin (chlorinated rubber) paints are preferred, and urethane paints are particularly preferred. Specifically, "Unimarine (trade name)" (China Paint Co., Ltd.,
Isocyanate crosslinked type two-component urethane resin topcoat), "Epiconmarine topcoat (trade name)", "Epiconmarine HB (trade name)" (China Paint Co., Ltd., modified polyamidoamine crosslinked type two-component epoxy resin) System top coat),
"Rabacs Topcoat (trade name)" (China Paint Co., Ltd., chlorinated polyolefin-based topcoat), "Acry 700 Topcoat (trade name)" (China Paint Co., Ltd., acrylic resin-based topcoat) and the like. be able to.

Each of the above paints for the water line portion and the outboard portion includes components which are usually blended with paints for hull outer plates, such as antifouling agents, plasticizers, hydrolysis regulators, pigments, solvents, and viscosities. Adjusters, other additives, and the like may be included. Further, the paint used for the top coat on the inner surface of the ship tank (ballast tank, cargo tank) is the anticorrosion paint used in the above-mentioned touch-up paint, and further disclosed in Japanese Patent Application No. 10-182291. Bisphenol-type epoxy resin-based anticorrosion coating compositions and urethane resin-based anticorrosion coating compositions. These anticorrosion coating compositions can also be used as overcoats for water lines and outboards.

This bisphenol-type epoxy resin-based anticorrosion coating composition has (i) an epoxy equivalent of 150 to 1000.
Bisphenol-type epoxy resin, (ii) a curing agent for an epoxy resin comprising a polyamidoamine, a polyamine or a modified product thereof, (iii) a coloring pigment of 0.3 to 5% by weight (solid content), and (iv) a light-transmitting property. Contains 25 to 50% by volume of inorganic filler (filler volume concentration).

Further, the urethane resin-based anticorrosion coating composition comprises:
(I) polyol and / or polythiol, (ii)
Polyisocyanate-based curing agent, (iii) coloring pigment 0.3 to
5% by weight (solid content), and (iv) 25-50% by volume of a light-transmitting inorganic filler (filler volume concentration).
When the bisphenol-type epoxy resin-based and urethane resin-based anticorrosion coating composition as described above is used, the anticorrosion coating composition has a hiding ratio of 0.94 or more and less than 1 at a desired dry coating film thickness t ₀ μm. Yes, contrast ratio of a dry film thickness t ₀ / 2μm is 0.70~0.90 (t ₀ is, 100-30
0), and the color difference (ΔE) between the dry coating film having a desired thickness t ₀ μm applied to the inner surface of the tank and the inner surface of the tank is 100. Then, the color difference (ΔE) between the coating film in the wet state of the coating portion and the inner surface of the tank is observed, and the amount of the anticorrosive coating composition is controlled so that the color difference (ΔE) becomes 90 or more.
According to this coating method, the coating thickness of the anticorrosion paint formed on the inner surface of the ship tank can be easily controlled.

Examples of the topcoat paint for onshore steel structures include oily (alkyd), phthalic acid resin, chlorinated polyolefin (chlorinated rubber), vinyl, acrylic, epoxy, urethane, and silicone. Examples include alkyd-based, acrylic silicone-based, and fluororesin-based topcoat paints. The above top coating may be performed by a conventional method such as airless spraying, air spraying, brush coating, or roller coating. Each of the above-mentioned paints can be appropriately diluted with a thinner or the like before use.

Second Method for Painting Ships or Steel Structures In a second method for painting ships or steel structures according to the present invention, repair painting of the surface of ships or steel structures assembled by welding steel materials is performed. After the surface is subjected to a water blast treatment for blasting the abrasive (A) together with water, a top coat is applied.

The water blasting method, the abrasive (A), the corrosion inhibitor (B) and the top coat in the second coating method are the first coating of the ship or steel structure according to the present invention described above. The method is the same as the water blast treatment method, the abrasive material (A), the corrosion inhibitor (B), and the top coat.

[0053]

The first aspect of the ship or steel structure according to the present invention.
According to the coating method, when a new ship or steel structure is manufactured, without damaging the primer coating formed by the primary surface treatment, the ship, heat scale adhered during construction of the steel structure, It is possible to completely or almost completely remove spatter, various foreign matters, corrosive substances, degraded parts of the primer coating and rust generated by damage to the primer coating, and after the removal of dust The working environment can be improved without reducing or necessitating the treatment, and the generation of return rust can be prevented without hindering the adhesion of the topcoat paint.

Further, according to the second method of coating a ship or a steel structure according to the present invention, when repairing and painting the surface of a ship or a steel structure, various foreign substances and corrosion that are attached to the steel material surface. Rust and rust can be completely or almost completely removed, and the working environment can be improved, and the generation of return rust can be prevented without impairing the adhesion of the topcoat paint. Can be.

The present invention utilizes a water blast treatment, and can form a top coat having the same physical properties as those of a top coat formed after conventional sand blast treatment or disk sander treatment. .

[0056]

EXAMPLES The present invention will be described below with reference to examples.
The present invention is not limited by these examples.

[0057]

Embodiment 1 Sandblasted 300 mm × 15
An inorganic zinc-based shop primer (trade name: Welbond H, China Paint Co., Ltd.)
Was coated so as to have a dry film thickness of 15 μm, and exposed outdoors for one month. The sand blasting was performed using No. 5 silica sand as an abrasive and at an air pressure of 0.5 MPa.

Next, immediately after the two coated steel plates were butt-welded, the welding wire was immediately touch-coated with an inorganic zinc-based shop primer (trade name: Wellbond H, manufactured by Chugoku Paint Co., Ltd.) and exposed outdoors for 3 months. . Next, the entire surface of the butt welded plate was subjected to a water blast treatment under the condition of a water pressure of 200 MPa, and then a tar epoxy-based anticorrosive paint (trade name: Viscon HB-20) was applied to the surface.
0, manufactured by China Paint Co., Ltd.) so as to have a dry film thickness of 200 μm and dried at 20 ° C. for 7 days to obtain a test piece for anticorrosion test.

The test piece for corrosion resistance test obtained as described above is cut with a cutter knife so as to reach a steel plate at a right angle to a welding line or a rusted portion, and is subjected to a 3% saline solution at 40 ° C. For 180 days, the degree of blistering of the coating film is ASTM D714-56, and the degree of rusting is ASTM D6.
Evaluated visually according to the following evaluation score according to 10-85,
The adhesiveness was determined by a cross-cut tape method (JIS K5400, 8.5.
2 based on the following evaluation score, and the sewage permeability of the coating film from the cut was measured.

Table 1 shows the results.

<Evaluation score of blister test> 10 points: no blister 9 points: 0.5 mm diameter blister was 0.2 of the total area of the test plate
8 points: 0.5 mm diameter blisters are 0.5% of the total area of the test plate
% 7 points: 0.5 mm to 1 mm diameter blisters are about 0.5% of the total area of the test plate 6 points: 1 mm to 2 mm diameter blisters are 0.5 to 1% of the total area of the test plate 5 points : 2 to 3 mm diameter blisters are about 1 to 5% of the total area of the test plate. 4 points: 3 mm to 5 mm diameter blisters are about 5 to 10% of the total area of the test plate. 3 points: 3 to 5 mm diameter blisters. Approximately 10 to 15% of the total area of the test plate 2 points: 3 to 5 mm diameter blisters are approximately 15 to 30% of the total area of the test plate 1 point: The blister rust area is 30% or more of the total area of the test plate

<Rating Test Evaluation Score (ASTMD610)
-85)> 10 points: no rust, or the rust area is less than 0.03% of the total area of the test plate 9 points: the rust area is 0.03% or more of the total area of the test plate.
Less than 1% 8 points: Rust area is 0.1% or more of the total area of test plate 0.3
7 points: Rust area is 0.3% or more and less than 1% of the total area of the test plate 6 points: Rust area is 1% or more and less than 3% of the total area of the test plate 5 points: Rust area is tested 3% or more and less than 10% of the total area of the plate 4 points: Rust area is 10% or more and less than 16% of the total area of the test plate 3 points: Rust area is 16% or more and less than 33% of the total area of the test plate 2 Point: Rust area is 33% or more and less than 50% of the total area of the test plate 1 point: Rust area is 50% or more of the total area of the test plate

<Evaluation score of cross cut test> 10 points: Each cut is thin and smooth on both sides, and there is no peeling at every intersection of the cut and the square. 9 points: Cuts are slightly thicker. Eight points: There was slight peeling at the intersection of the cuts, and there was no peeling at a glance of the square, and the area of the defective portion was within 5% of the area of the entire square. 7 points: Peeling was found on both sides of the cut and at the intersection, and the area of the defective portion was less than 5% of the total square area. 6 points: Peeling was found on both sides of the cut and the intersection, and the area of the defective portion was 5% or more and less than 15% of the total square area. 5 points: The width of peeling due to cuts is wider than “6 points”, and the area of the defective portion is 15% or more and less than 25% of the entire square area. 4 points: The width of the peeling due to the cut is wide, and the area of the defective portion is 25% or more and less than 35% of the total square area. 3 points: Each square was peeled at a glance, and its area was within 35% of the total square area. 2 points: Peeling due to cuts is larger than “3 points”, and the area of the defective portion is 35% or more and less than 50% of the entire square area. 1 point: Peeling due to cuts is larger than “2 points”, and the area thereof is 50% or more and less than 70% of the entire square area. 0 point: The area of peeling is 70% or more of the area of all squares.

[0064]

Example 2 In Example 1, the abrasive material (garnet particles 90) was used instead of the water blast treatment of Example 1.
(% By weight and 10% by weight of zinc particles), water-blasting was performed under the condition of a water pressure of 20 MPa using water to obtain a test piece for anticorrosion test.

Using the anticorrosion test thus obtained, the degree of blistering, rusting and adhesion of the coating film were evaluated in the same manner as in Example 1. The sewage permeability of the coating film was measured.

Table 1 shows the results.

[0067]

Example 3 Sandblasted 300 mm × 15
An inorganic zinc-based shop primer (trade name: Welbond H, China Paint Co., Ltd.)
Was coated so as to have a dry film thickness of 15 μm, and exposed outdoors for one month. The sand blasting was performed using No. 5 silica sand as an abrasive and at an air pressure of 0.5 MPa.

Next, the two coated steel plates were butt-welded, and further exposed outdoors for 3 months to generate rust at the welded portions. Next, after performing a water blast treatment on the entire surface of the butt welded plate under the condition of a water pressure of 200 MPa, a functional anticorrosive paint (trade name: Bismax,
(China Paint Co., Ltd.) was touch-up painted.

Then, a tar epoxy-based anticorrosive paint (trade name: Viscon HB-20) was applied to the surface of the butt welded plate.
0, manufactured by China Paint Co., Ltd.) so as to have a dry film thickness of 200 μm and dried at 20 ° C. for 7 days to obtain a test piece for anticorrosion test. Using the test for corrosion resistance test obtained as described above, the degree of blistering, the degree of rusting, and the adhesion of the coating film were evaluated in the same manner as in Example 1. The penetration was measured.

Table 1 shows the results.

[0071]

Comparative Example 1 Sandblasted 300 mm × 15
An inorganic zinc-based shop primer (trade name: Welbond H, China Paint Co., Ltd.)
Was coated so as to have a dry film thickness of 15 μm, and exposed outdoors for one month. The sand blasting was performed using No. 5 silica sand as an abrasive and at an air pressure of 0.5 MPa.

Next, the two coated steel plates were butt-welded and exposed outdoors for another three months to generate rust at the welded portions. Next, after sandblasting is applied to the entire surface of the butt welded plate, a tar epoxy-based anticorrosive paint (trade name: Viscon HB-200, manufactured by China Paint Co., Ltd.) is applied to the surface so that the dry film thickness becomes 200 μm. And dried at 20 ° C. for 7 days to obtain a test piece for corrosion resistance test. This sand blasting was also performed using No. 5 silica sand as an abrasive and at an air pressure of 0.5 MPa.

Using the test piece for corrosion resistance test obtained as described above, the degree of blistering, the degree of rusting, and the adhesion of the coating film were evaluated in the same manner as in Example 1. Of the coating was measured. Table 1 shows the results.

[0074]

Comparative Example 2 A test piece for an anticorrosion test was prepared in the same manner as in Comparative Example 1, except that water blasting was performed under the condition of a water pressure of 200 MPa instead of sandblasting performed on the butt welded plate. Obtained. Using the test piece for corrosion resistance test obtained as described above, the degree of blistering, the degree of rusting, and the adhesion of the coating film were evaluated in the same manner as in Example 1, and the coating film from the cut portion was further evaluated. The sewage permeability was measured.

Table 1 shows the results.

[0076]

Comparative Example 3 A test piece for an anticorrosion test was obtained in the same manner as in Comparative Example 1, except that the sand blast treatment applied to the butt welded plate was not performed. Using the test piece for corrosion resistance test obtained as described above, Example 1
In the same manner as in the above, the degree of blistering, the degree of rusting, and the adhesion of the coating film were evaluated, and the sewage permeability of the coating film from the cut was measured.

Table 1 shows the results.

[0078]

Example 4 Sandblasted 300 mm × 15
An inorganic zinc-based shop primer (trade name: Welbond H, China Paint Co., Ltd.)
Co., Ltd.) to a dry film thickness of 15 μm, and then a tar epoxy-based anticorrosion paint (trade name VISCON HB-20)
0, manufactured by Chugoku Paint Co., Ltd.) to a dry film thickness of 200 μm. The sand blasting was performed using No. 5 silica sand as an abrasive and at an air pressure of 0.5 MPa.

Next, the central part of the coated steel sheet was 30 mm
The coating film was peeled off to the width, immersed in 3% saline for 3 months, and partially rusted. Then, on the rusted part of this coated steel sheet,
Abrasives (90% by weight garnet particles and 10 zinc particles)
(% By weight), water blasting was performed at a water pressure of 20 MPa, and then a tar epoxy-based anticorrosive paint (trade name: Viscon HB-200, manufactured by Chugoku Paint Co., Ltd.) having a dry film thickness of 200 μm. It was then coated and dried at 20 ° C. for 7 days to obtain a test piece for corrosion resistance test.

Using the test piece for corrosion resistance test obtained as described above, the degree of blistering, the degree of rusting, and the adhesion of the coating film were evaluated in the same manner as in Example 1. Of the coating was measured. Table 1 shows the results.

[0081]

Comparative Example 4 A test piece for an anticorrosion test was obtained in the same manner as in Example 4 except that water blasting was performed under the condition of a water pressure of 200 MPa instead of the water blasting of Example 4. Was. Using the test piece for corrosion resistance test obtained as described above, the degree of blistering, the degree of rusting, and the adhesion of the coating film were evaluated in the same manner as in Example 1, and the coating film from the cut portion was further evaluated. The sewage permeability was measured.

Table 1 shows the results.

[0083]

[Table 1]

(Improvement of coating film performance and improvement of coating environment according to the present invention) The outer plate portion, deck portion and ballast tank portion of a 258,000 ton tanker constructed as a new ship were constructed by the coating method of the present invention described below. In the case, the degree of improvement in the following items, the conventional coating method -1 shown below
(Sand, grit blasting) and coating method-2 (power tool processing (wire brush, disk sander processing)).

The coating method of the present invention; the rust-generating part of the welding wire is subjected to water blast treatment until it reaches the grade of ISO Sa2.5, and the general parts other than the rust-generating part are:
Dust, dirt, and other dust were removed by water sweep blasting. This water blasting process
As an abrasive, a mixture of 90% by weight of garnet particles and 10% by weight of zinc dust was used at a ratio of 5% by volume to water. Further, the water sweep blast treatment was performed using only water without using an abrasive material.

After finishing these treatments, the treated surfaces were coated with a tar epoxy-based anticorrosive paint. Conventional coating method-1: The rust-generating portion of the welding wire is mainly subjected to drive blast treatment using copper lumps as abrasive material until it reaches the grade of ISO Sa2.5, and the general portion other than the rust-generating portion is dusty. , Dust and other dust were removed by sweep blasting. After these treatments, the treated surface was coated with a tar epoxy-based anticorrosion paint.

Conventional coating method-2: The rust-generating part of the welding wire is mainly treated with a disk sander until the grade reaches ISO St-3, and the general part other than the rust-generating part is dust, dirt or other dust. Was removed by a simple disk sanding process. After these treatments, the treated surface was coated with a tar epoxy-based anticorrosion paint.

The numerical value of the degree of improvement (improvement) was calculated from the conventional coating method-1 and the conventional coating method-2, with the coating method of the present invention being 100. 1. Improvement of coating film performance (1) Persistence of inorganic zinc-based shop primer Calculated from the residual amount of inorganic zinc-based shop primer by various surface treatments (the smaller the value obtained from the following formula, the lower the residual property is. Shown).

Calculation formula; (Attached amount of shop primer before surface treatment) ÷ (Attached amount of shop primer before surface treatment) × 100 (2) Efficiency of removing corrosive substances in small pits or holes Various surface treatments It was calculated from the remaining amount of the corrosive substance in the later pits or holes (the smaller the value obtained by the following formula, the lower the removal efficiency).

(Amount of corrosive substance removed from pits and holes per fixed area after surface treatment) / (amount of corrosive substance from pits and holes per fixed area before surface treatment) × 100 (3) ) Uniform surface treatment property Calculated from the grade of removal of rust, dust, corrosive substances, etc. on the treated surface (the smaller the value obtained from the following formula, the lower the uniform surface treatment property).

Calculation formula: (Area for removing rust, dust, and corrosive substances per fixed area after surface treatment) ÷ (Rust, dust, per unit area before surface treatment)
(4) Turning property after surface treatment Calculated from the degree of turning after surface treatment (the smaller the value obtained from the following formula, the lower the turning property is). .

Calculation formula; (Area without turning after surface treatment) ÷
(Area without turning before surface treatment) x 1
(5) Adhesion of Top Coating Paint The adhesion was calculated by examining the adhesion of the top coating (the smaller the value obtained from the following formula, the lower the adhesion). That is, the adhesion after the lapse of time was evaluated by the evaluation score of the above-described cross-cut test. 2. Improvement of painting work environment (1) Dust scatterability Calculated by measuring the amount of scattered dust around the work place (the smaller the value obtained from the following formula, the larger the dust scatter).

Calculation formula; (Amount of scattered dust in the coating method of the present invention) / (Amount of scattered dust in the conventional coating method-1 or 2) × 100 (2) Dust post-processing property (The smaller the value obtained from the following formula, the larger the post-processing is).

(Dust treatment area in the conventional method) ÷ (Dust treatment area in the present invention) × 100 (3) Simultaneous rapid workability of surface treatment work and cleaning work Lap work time of surface treatment work and cleaning work (The smaller the value obtained from the following formula, the shorter the lap work time is.)

(Lap time according to the conventional method) ÷ (Lap time according to the present invention) × 100 (4) Ease of processing work Calculated from various protective measures such as dustproof measures, waterproof measures, high-pressure injection measures, etc. (The smaller the value obtained by the following formula, the worse the workability is.)

Calculation formula: (man-hours for various countermeasures of the present invention) ÷ (man-hours for conventional countermeasures) ×
100 (5) Processing Efficiency The processing efficiency was calculated from the processing area per unit time (the smaller the value obtained from the following formula, the lower the efficiency).

(Calculation formula: (processing area per fixed time according to the conventional method)) ((processing area per certain time according to the present invention) × 100 (6) Economics of processing Maintenance cost, depreciation cost, personnel cost, etc. of equipment (The smaller the value obtained from the following formula, the lower the economic efficiency.)

Calculation formula: (Various costs per unit area according to the present invention) / (Various costs per unit area according to the conventional method) × 100 The above calculation results are shown in Table 2.

[0099]

[Table 2]

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Hidesuke Yoshimura 2-1-1, Uchisaiwai-cho, Chiyoda-ku, Tokyo Iino Building Inside Chugoku Paint Co., Ltd. (72) Inventor Hisao Aikawa 1 Meiji Shinkai 1 in Otake City, Hiroshima Prefecture Address 7 China Paint Co., Ltd. F term (reference) 4D075 BB01X BB04X BB20X BB93X CA33 DA06 DA27 DA35 DB02 DC05 DC08 EB01 EC10 EC15

Claims (13)

[Claims] 1. A ship or steel, characterized in that a water blast treatment is applied to the entire surface of a ship or steel structure assembled by welding a steel material having a zinc-based shop primer applied to the surface thereof, and then a top coat is applied. How to paint the structure. 2. A zinc-based anticorrosive paint is applied to a ship or a steel structure which is assembled by welding a steel material coated with a zinc-based shop primer on a surface of the ship or steel structure, where the zinc-based anticorrosive paint is touched up. The coating method according to claim 1, wherein a water blast treatment is applied to the entire surface of the ship or the steel structure. 3. A water blasting treatment is applied to the entire surface of a ship or a steel structure assembled by welding a steel material having a surface coated with a zinc-based shop primer, and then a coating damaged portion of the zinc-based shop primer is removed. The coating method according to claim 1 or 2, wherein after applying an anticorrosive paint having affinity for the base material and the topcoat paint to the weld seam portion and the sharp edge portion, the topcoat paint is applied. 4. The coating method according to claim 1, wherein the abrasive material (A) is blasted together with water during the water blast treatment. 5. The coating method according to claim 4, wherein said abrasive material (A) is an abrasive material comprising particles (a1) of a metal base lower than iron. 6. A polishing material according to claim 1, wherein said polishing material (A) is a mixture of particles (a1) of a metal base less than iron and inorganic fine particles (a2) other than a metal. 4. The coating method according to 4. 7. The coating method according to claim 1, wherein water containing a corrosion inhibitor (B) is used during the water blasting. 8. The coating method according to claim 1, wherein a water pressure in said water blasting treatment is 0.1 to 300 MPa. 9. In repair painting of a ship or steel structure surface assembled by welding steel materials, the surface is subjected to a water blast treatment for blasting the abrasive material (A) together with water, and then a top coat is applied. A method for painting a ship or a steel structure, comprising: 10. The coating method according to claim 9, wherein said abrasive material (A) is an abrasive material comprising particles (a1) of a metal lower than iron. 11. The abrasive material according to claim 1, wherein said abrasive material (A) is a mixture of particles (a1) of a metal base lower than iron and inorganic fine particles (a2) other than a metal. 9. The coating method according to 9. 12. The coating method according to claim 9, wherein water containing a corrosion inhibitor (B) is used during the water blast treatment. 13. The coating method according to claim 9, wherein a water pressure in said water blasting treatment is 0.1 to 300 MPa.